Sigourney Weaver doesn't think sci-fi films ''get enough respect''.

The 65-year-old actress - who is, perhaps, best known for playing Ellen Ripley in the 'Alien' franchise - has hit out at critics of the genre, but thinks attitude towards such films will change in the coming years.

Weaver, who stars in new movie 'Chappie', said: ''It is a genre that I think doesn't get enough respect when you consider how many issues sci-fi brings up that we need to deal with.''

Asked why the genre is so often overlooked for Academy Awards, she told Digital Spy: ''I think part of it is the Academy is mostly people like me who are over a certain age and they're still probably looking for the more conventional movie.

''I think all that's going to change because some of the work being done in sci-fi is some of the most interesting, provocative work out there.''

Meanwhile, Weaver and 'Chappie' director Neill Blomkamp are set to reunite for a new 'Alien' movie.

The director said the film will feel like the ''genetic sibling of Aliens'', meaning it will disregard 'Alien 3' and 'Alien: Resurrection' and will instead carry on from the James Cameron-directed 'Aliens'.

He explained: ''I want this film to feel like it's literally the genetic sibling of Aliens. So it's Alien, Aliens, and then this movie.''